Gyratory crusher



Oct. 6, 1970 D K R ET AL 3,532,277

GYRATORY CRUSHER Filed May 20, 1968 2 Sheets-Sheet l INVEN TOR$:

H. DECKER ET AL GYRATORY CRUSHER Oct. 6, 1970 2 Sheets-Sheet Filed May 20, 1968 United States Patent 01 Ffice 3,532,277 Patented Oct. 6, 1970 Int. (:1. 1362c 2/04 U.S. Cl. 241-208 7 Claims ABSTRACT OF THE DISCLOSURE A gyratory crusher with an upper feed opening and a fixedly mounted annular crushing tool into which extends from below a rotary conical crusher head so as to form an annular crushing gap between the fixed crushing tool and the rotary crusher head. The rotary crusher head is movably mounted on the upper end of a vertical shaft which extends through a stationary tubular main shaft and carries a set of pretensioned springs subjected to a hydraulic pressure exerted by a movable piston in a hydraulic cylinder formed in said tubular main shaft. Upon raising and lowering the piston in said hydraulic cylinder the size of the annular crushing gap may be decreased and increased respectively.

The invention relates to a gyratory crusher, the crushing head of which is supported by a pretensioned spring arranged in a center bore.

, Such gyratory crushers according to the German Pat. No. 1,017,005 are provided with means for pretensioning the spring which means comprise a nut and a thread on a pin centrically extending through a set of annular springs. The required strong pretensioning of the spring necessitates, particularly in larger machine units, additional devices for compressing the spring as a turning of the nut under load cannot be done. Such an additional or auxiliary device consists mostly of at least two tension rods and two crossbars between which are clamped a hydraulic press, a pressure measuring gauge and the set of springs. Such auxiliary devices are extremely cumbersome and may weigh up to several tons. Their transportation and handling at the work location of the crusher is costly, difficult, cumbersome and not without hazards.

The mentioned gyratory crusher is also eqnuipped with a thread operated gearing and gear wheels for the purpose of adjusting the width of the crushing gap. Due to the occurring strong crushing forces and frictional resistances this adjustment is done mostly when the machine runs idle. If a blocking of the crushing cone occurs by an unbreakable item, it is--particularly in larger machines-frequently not possible to lower the crushing cone by means of the adjustment gearing, but the top section has to be lifted after all the housing screws have been loosened and upon clearing of the crushing space the screws have to be tightened again.

In crushers of the aforedescribed type the adjustment gearing due to the large diameter of the gear wheels and their positioning below the set of springs is for the purpose of mounting and dismounting accessible only from a space under the machine. This calls for additional structural and preparative measures. If the mechanical adjustment gearing is to be effective under all circumstances, an additional transmission and substantially increased overall dimensions are required and this will result in a still more elaborate and voluminous structure.

It is the object of the invention to create a simple and space-saving crushing gap adjustment gearing which also can be operated under load as well as in the event of blocking and which is also capable of producing and controlling the pretensioning of the spring. For the purpose of inspection and repair work, the individual gearing parts are removable from the machine from above so that the walk-in space under the machine can be practically eliminated.

This is accomplished according to the invention in that a hydraulic cylinder-piston unit transmitting the occurring longitudinal forces is arranged above or below the spring.

From the German patent publication 1,219,775 it is known to hydraulically support the cone aggregate and this is always done in conjunction with a pneumatic spring means. However, this arrangement is no satisfactory solution yet as to simplicity, dependability and favorable spring conditions due to a high rest friction and dampening of the annular springs. A complete solution should also provide for an independence from restrictions due to flow velocities when using hydraulic or hydraulic-pneumatic auxiliary spring systems.

The use of the hydraulic adjustment gearing comprising a cylinder-piston unit in combination with mechanical spring means according to the invention not only leads to a simplified and less expensive structure, but-as will be expounded later onalso eliminates the use of heavy and costly auxiliary devices for pretensioning the mechanical spring. A further advantage is the reduced installation height which results in savings in the erection of plant buildings.

These and other objects of the invention will become apparent from two embodiments of the invention illustrated in the accompanying drawings, in which:

FIG. 1 is a vertical longitudinal sectional view of a gyratory crusher provided with a cylinder-piston unit arranged below the pretensioned spring, and

FIG. 2 is a vertical sectional view of a gyratory crusher provided with a cylinder-piston unit arranged above the pretensioned spring.

Referring to FIG. 1, the stationary housing of a gymtory crusher comprises a top portion 1 having an upper feed opening 2, a fixedly mounted crushing tool 3 just belowd said feed opening, and the machine frame 4 which contains the rotatable crushing cone and the parts supporting and rotating the same. The crushing cone 5 rests on a supporting cone 6 in the hollow interior of which is arranged the calotte 7 of the side bearing. The transverse forces acting on the cone are taken up by the cylindrical surface 8 engaging the eccentric sleeve 10 driven by bevel gear 9. The eccentric sleeve 10 is rotatably supported by the tubular main shaft 11 secured to the frame 4. The bearing pan 12 of the longitudinal bearing rests on the upper end of the shaft 13 which is axially slidable in the center bore of the stationary tubular main shaft 11. A set of pretensioned annular springs 15 is arranged between the shaft 13 and a ring 14. The ring 14 is slidable on a center pin 16 connected to the lower end of the shaft 13 and transfers the spring bias to a collar 14a fixed to the pin 16. The lower end face of the ring 14 engages the upward facing end face surface of a hydraulic piston 17. The upper end of the piston 17 is recessed in order to allow enough freedom of movement for the center pin 16 during the resilient movement of the cone aggregate 5, 6, 7. The diameter of the piston is such that upon the dismounting of the cone aggregate and the compression spring 15 it may freely be pulled upwardly and be removed from the bore of the tubular main shaft 11. The piston 17 is slidably fitted in a cylindrical tube 18 inserted in the bore of the tubular main shaft 11 or may also be slidably fitted within the bore itself and sealed in known manner. Pressure fluid is fed to and discharged from the cylindrical bore 19 in the tube 18 in any 'known manner. The level of the oil filling determines the position of the piston and therewith the width of the annular crushing gap 20 formed between the parts 3 and 5. For protection against excess forces when the intended length of the spring movement is exceeded, a pressure relief valve may be connected to the interior of the cylinder formed by the tube 18. The great advantage of the hydraulic abutment resides in addition to simplification of construction as compared to a mechanical adjustment gearing in the relative ease with which the great force required for lifting the heavy cone aggregate is produced by means of a correspondingly dimensioned pressure medium pump and in that a lowering of the piston also in cases which the machine is blocked by a sizable unbreakable alien body is readily eifected by a discharge of the pressure medium. A lowering of the piston and thus a relief of the crushing gap is frequently not possible with mechanical adjustment because the entrance of an alien body may be followed by a strong decrease in speed which does compress the spring due to the effect of the centrifugal masses but eventually leads to a standstill. An adjustment gearing under this kind of load is not releasable just by a turning operation.

When several gyratory crushers are simultaneously operated, it is of advantage when the gap widths of all crushers can be regulated from a single control center. For this purpose the cylinders 18, 19 of all crushers are connected with the control center by way of a pressure medium pipe. The control center in addition to a number of hydraulic switch valves may be provided with only one pressure medium pump which according to necessity is hooked up to one of the cylinders 18, 19. The capacity of the pump may be small since the volume of the cylinder interior is only small, too. Accordingly, the pressure medium pipes may also be of small diameter. All

these points contribute to savings in installation and maintenance of the machine. It will be noted that the small diameter of the pressure medium pipe and thus the smaller quantity of pressure medium that is compressible will not cause a lessening of the rigidity of the hydraulic abutment of the cone aggregate The lubricant required for lubricating the set of springs and the bearings 7, 8 is conveyed under pressure and is applied by way of a radial port 20".

The interior of the cylinder 18, 19 is at its lower end pressure-tight closed by a cover 18. The pressure medium is supplied from below by means of a trombone pipe 21 which preferably follows the piston movement in that it is kept in steady contact with the bottom of the up and down travelling piston 17, by means of a spring 22 so that a discharge of pressure medium always takes place from the highest point of the interior of the cylinder 18, 19 and any undesirable air bubbles are thus safely eliminated. By the elimination of the mechanical adjustment gearing it is possible to further reduce the structural height and thus the height of the space required for installation.

FIG. 2 illustrates an embodiment of the invention in which the cylinder-piston unit is positioned on top. The cylinder space 23 is formed by an enlarged bore portion in the shaft 24 of the longitudinal bearing 25, and the upper end of the center pin 26 of the set of springs 15 which is formed like a piston is sealingly guided in the cylinder space 23. The pressure medium is supplied by means of a longitudinal passage 27 in the center pin 26. An air relief means for the cylinder space 23 and a lubricant supply means may be installed analogous to the embodiment shown in FIG. 1. The properties and advantages of FIG. 1 are also true of the embodiment according to FIG. 2.

An important operational measure is the checking of the set of springs 15 for the presence of the required spring bias. In order to carry out this inspection, the cone aggregate is blocked against an upward displacement, which may be done, for instance, by placing several steel wedges into the annular crushing gap 20. Then by means of the pump the pressure medium is supplied until the piston 17, 26 starts to move against the spring force. The product of the fluid pressure and the piston diameter is then a measure for the spring bias. From the pressure difference between the rising and lowering of the piston may be calculated the frictional resistance value of the set of springs.

The cylinder-piston unit 17, 18 and 24, 26 also serves for producing the spring bias after a new set of springs has been installed. This is done in the embodiment according to FIG. 2 in a simple manner in that upon installation of the cone aggregate and blocking of the longitudinal movement of the cone, as described in the foregoing the required pretensioning is imparted to the set of springs 15 by compressing the spring by means of the cylinder-piston unit 24, 26. The space thus produced between the ring 14 and the collar 14a is filled by an intermediary ring 14b of suitable height before the collar 14a is fixedly secured to the center pin 16. Subsequently, the fluid pressure may be reduced and the blocking may be removed. After adjusting the crushing gap 20 to the desired width by supplying the cylinder 23 with a controlled amount of pressure fluid the crusher is ready for operation.

Since in the embodiment of FIG. 1 the center pin 16 is not accessible, the spring assembly when pretensioning a new spring has to be inserted upside down into the center bore of the stationary main shaft 11. The shaft 13 then rests on the upper end face of the piston 17. The ring 14 on the now upwards facing end of the spring set 15 is then fixedly supported with respect to the housing, for instance by means of a crossbar secured to the upper edge of the machine frame 4. Now the supply of pressure fluid is turned on until the desired degree of biasing is reached. The space thus produced between the ring 14 and the annular collar 14a is filled by a suitable intermediary ring not illustrated prior to finally securing the collar 14a to the pin 16. If the end of the pin 16 is provided with a thread and the part 14a is in the form of a nut, the latter may be screwed onto the pin 16 and locked. The thus prepared set of springs is then installed into its operative position.

Additional structural parts are required for inserting the hollow shaft 11 into the hub of the housing 4 and removing it therefrom and the previously described spring tensioning means will simultaneously also furnish some of these parts.

The values of the forces for installing the preferably conical seat lie above the spring force limiting values in order to prevent the occurrence of displacements when the seat is elastically stressed.

When employing the hydraulic adjustment means ac cording to the invention the insertion of the shaft 11 may be done by means of its cylinder-piston unit, namely when for instance the spring 15 is replaced by a rigid distance pipe and the support is provided by a stationary auxiliary crossbar for which part of the top portion 1 may be utilized.

A removal of the fixedly mounted main shaft 11, as a rule, is not necessary and will occur only occasionally. If, however, the piston-cylinder unit is constructed as a separate, independent unit (not illustrated) then by a corresponding rearrangement and some minor additional parts the removal may also be accomplished.

The apparatus according to the invention, then makes the acquisition of an auxiliary hydraulic apparatus producing pressures from about to 2 00 tons superfluous since the incorporated hydraulic unit is anyway designed for meeting the required forces.

The described methods particularly facilitate the jobs of mounting, inspection and repair and the moving of heavy clumsy tensioning devices to the work location of the machine becomes unnecessary. The hydraulic device thus has a multi-purpose function.

A further advantage of the invention over known crushers having a hydraulic abutment and pneumatic spring means is that the pistons 17, 26 are at rest with respect to the cylinders 18, 24 during operation. Therefore, the action of the springs will not tax the piston seals which are under high pressure and therefore no wear will occur.

While the description and the exemplary embodiments relate to a gyratory crusher bearing system, the scope of the invention is not limited to such system.

What we claim is:

1. A device for tensioning and testing of a spring which in a gyratory crusher provided with a vertically disposed tubular main shaft is ararnged in the bore of said tubular main shaft and yieldably acts against the forces acting from above on the crushing head of said gyratory crusher, wherein the improvement comprises a hydraulic unit including a hydraulic cylinder and a slidable piston arranged in axial alignment with said spring and is effective to act against the forces acting from above on said crusher head.

2. A device according to claim 1, in which said gyratory crusher has a bearing for movably supporting said crusher head, said hydraulic cylinder being formed by an axial bore in said bearing which extends into the upper end of said tubular mainshaft, while said slidable piston in said bore of said hydraulic cylinder engages the upper end of said spring.

3. A device according to claim- 1, in which said hydraulic cylinder is arranged at the lower end of said tubular main shaft in axial alignment therewith and that the lower end of said spring is in engagement with said slidable piston in said hydraulic cylinder.

4. A device according to claim 1, in which the diameter of the bore of the tubular main shaft is substantially the same as the bore of the hydraulic cylinder in which said piston is slidable.

5. A device according to claim 1 in which said gyratory crusher has a bearing for movably supporting said crusher head, said bearing being mounted on the upper end of a shaft which is axially slidably mounted in the upper end of the bore in said tubular main shaft, while said piston in said hydraulic cylinder has a diameter which is not greater than the diameter of said shaft.

6. A device according to claim 1 including a hydraulic pressure medium pipe connected to said hydraulic cylinder and terminating close to the highest point of the cylinder space in which said piston is arranged.

7. A device according to claim 6 including means for slidably mounting a portion of said hydraulic pressure medium pipe, and a spring for yieldably urging the discharge end of said pipe portion in engagement with an end face of said slidable piston in said hydraulic cylinder.

References Cited UNITED STATES PATENTS 2,079,882 5/ 1937 Traylor 241-2-15 X 2,667,309 1/1954 Becker 24121l 2,833,486 5/1958 MacLeod 241-215 3,227,381 1/1966 Golucke et al. r 241-208 3,372,881 3/1968 Winter 241208 3,417,932 12/ 1968 Patterson 241--2J08 FOREIGN PATENTS 770,261 3/ 1957 Great Britain.

JAMES M. MEISTER, Primary Examiner 

